probe(redirected from Marquis probe)
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(Sense 2) Probes are essential tools for DNA analysis. Every DNA molecule possesses some unique nucleotide sequences that differentiate it from all others. A probe is a relatively short fabricated fragment of DNA that matches, in lock-and-key fashion, a nucleotide sequence unique to the material that is being sought. Probes are used to test for the presence of cloned genes in bacterial or yeast colonies, for specific nucleotide sequences in samples of DNA, or for specific genes on chromosomes.
probeSurgery Explorer A long, thin, usually metal instrument with a blunt or bulbous tip which is used to poke around in cavities, fistulae, sinuses, and wounds
probeAny slender, usually blunt-ended instrument used to explore a passageway, cavity or wound.
- a defined NUCLEIC ACID MOLECULE that can be used in MOLECULAR HYBRIDIZATION procedures to identify specific nucleic acid sequences that are complementary to it, by virtue of a LABEL generally carried by the probe. The label may be radioactive and detected by an AUTORADIO GRAPH, or non-radioactive, such as a fluorochrome, which could be detected by FLUORESCENCE. Under the right conditions the probe will hybridize only with a perfectly matching nucleic acid target molecule. The hybrid thus formed can then be detected by the appropriate method, depending upon the label on the probe. The probe may be DNA, RNA or a synthetic OLIGONUCLEOTIDE. Nucleic acid probes have a wide range of applications, such as in the detection of MICROORGANISMS in clinical specimens, in food and water samples, in the detection of genetic DISEASES (see RFLPs and in the identification of individuals (see FINGERPRINTING).
- a labelled molecule, such as a MONOCLONAL ANTIBODY, that can bind to a specific PROTEIN being searched for. The label permits detection.